This invention relates generally to gearshift assemblies for motorized vehicle manual transmissions and specifically to a socket and a gearshift lever having an upper ball and a lower ball thereby providing for different pivot ratios in crossover and linear directions.
As is known, conventional manual transmissions are typically equipped with a gearshift assembly which permits a vehicle operator to selectively shift between various forward ratio gears and a reverse gear. The gearshift assembly includes a tower housing secured to an exterior surface of the transmission casing and a gearshift lever that is operably coupled to a socket and shift rail. Typically, such an assembly has a standardized shift pattern such that the shift lever is movable along a neutral crossover path to a plurality of preselected gate positions, each of which defines a linear shift plane for a pair of ratio gears. Most commonly, the gate position located at one end of the neutral crossover path defines the linear shift plane between the first and second gears while the gate position at the opposite end of the neutral crossover path usually defines a shift plane between the highest forward ratio gear position (i.e., fifth gear) and the reverse gear position.
These traditional gearshift levers have a pivot mechanism and a single lower ball, such that the distance therebetween defines a pivot ratio. Thus, pivotal movement along the neutral crossover path and the linear shift planes, as dictated by the gearshift lever pivot ratio causes rotational and translating movement of the socket and shift rail. However, conventional crossover and linear pivot ratios must be identical due to the common pivot point and singular ball. As such, it is often awkward for the vehicle operator to manipulate the gearshift lever. While such design constraints have herebefore been recognized, most viable alternatives would require portions of the high-volume manual transmissions to be redesigned and/or retooled.